/* 全局样式重置和基础设置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #4a90e2;
    --secondary-color: #f5a623;
    --text-color: #333;
    --text-light: #666;
    --bg-color: #f8f9fa;
    --white: #fff;
    --border-radius: 8px;
    --box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
    --navbar-bg: #fff;
    --card-bg: #fff;
}

/* 黑暗模式变量 */
[data-theme="dark"] {
    --primary-color: #6ba4e8;
    --secondary-color: #ffb443;
    --text-color: #e0e0e0;
    --text-light: #a0a0a0;
    --bg-color: #121212;
    --white: #1e1e1e;
    --navbar-bg: #1e1e1e;
    --card-bg: #2c2c2c;
    --box-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
}

/* 深色模式下的渐变背景 */
[data-theme="dark"] body {
    background: linear-gradient(135deg, #121212 0%, #1e293b 100%);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background: linear-gradient(135deg, #f8f9fa 0%, #e8f0ff 100%);
    transition: background 0.3s ease, color 0.3s ease;
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 导航栏样式 */
.navbar {
    background-color: var(--navbar-bg);
    box-shadow: var(--box-shadow);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    transition: background-color 0.3s ease;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 20px;
}

.logo {
    display: flex;
    align-items: center;
}

.logo-link {
    display: flex;
    align-items: center;
    text-decoration: none;
}

.logo-img {
    height: 36px;
    width: auto;
    display: block;
    margin-right: 10px;
}

.logo-text {
    font-size: 24px;
    color: var(--primary-color);
    font-weight: 600;
    white-space: nowrap;
    transition: color 0.3s ease;
}

.nav-container {
    display: flex;
    align-items: center;
    gap: 20px;
}

.nav-menu {
    display: flex;
    list-style: none;
}

.nav-menu li {
    margin-left: 30px;
}

.nav-menu a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: var(--transition);
}

.nav-menu a:hover {
    color: var(--primary-color);
}

/* 黑暗模式切换按钮样式 */
.dark-mode-toggle {
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 8px;
    border-radius: 50%;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
}

.dark-mode-toggle:hover {
    background-color: rgba(0, 0, 0, 0.1);
    transform: scale(1.1);
}

.dark-mode-toggle .toggle-icon {
    font-size: 20px;
    transition: transform 0.3s ease;
}

.dark-mode-toggle:hover .toggle-icon {
    transform: rotate(15deg);
}

[data-theme="dark"] .dark-mode-toggle:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

[data-theme="dark"] .dark-mode-toggle .toggle-icon {
    content: "☀️";
}

/* 黑暗模式下的logo文字 */
[data-theme="dark"] .logo-text {
    color: var(--primary-color);
}

/* 确保logo链接不影响文字颜色 */
.logo-link {
    text-decoration: none;
    color: inherit;
}

/* 英雄区域样式 */
.hero {
    background: linear-gradient(135deg, var(--bg-color) 0%, var(--white) 100%);
    padding: 110px 0 80px;
    margin-top: 54px;
    position: relative;
    overflow: hidden;
    transition: background 0.3s ease;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(74, 144, 226, 0.1) 0%, rgba(255, 255, 255, 0) 70%);
    border-radius: 50%;
    z-index: 0;
    transition: background 0.3s ease;
}

[data-theme="dark"] .hero::before {
    background: radial-gradient(circle, rgba(107, 164, 232, 0.2) 0%, rgba(0, 0, 0, 0) 70%);
}

.hero .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: relative;
    z-index: 1;
}

.hero-content {
    flex: 1;
    max-width: 500px;
    animation: slideInLeft 0.8s ease-out;
}

@keyframes slideInLeft {
    from {
        opacity: 0;
        transform: translateX(-50px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.hero h1 {
    font-size: 52px;
    font-weight: 800;
    margin-bottom: 15px;
    color: var(--primary-color);
    line-height: 1.1;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
}

.hero h2 {
    font-size: 36px;
    font-weight: 700;
    margin-bottom: 25px;
    line-height: 1.2;
    color: var(--text-color);
}

.hero p {
    font-size: 18px;
    color: var(--text-light);
    margin-bottom: 35px;
    line-height: 1.7;
}

.hero-download {
    margin-top: 50px;
}

.hero-download h3 {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 20px;
    color: var(--primary-color);
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: 0 2px 4px rgba(74, 144, 226, 0.1);
    letter-spacing: 0.5px;
    display: inline-block;
    padding: 8px 0;
    position: relative;
}

.hero-download h3::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: linear-gradient(90deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    border-radius: 2px;
    transform: scaleX(0.6);
    transform-origin: left center;
    transition: transform 0.3s ease;
}

.hero-download h3:hover::after {
    transform: scaleX(1);
}

.download-buttons {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
    justify-content: center;
    margin-top: 20px;
}

.btn {
    display: inline-block;
    padding: 12px 24px;
    border-radius: var(--border-radius);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
    cursor: pointer;
}

.btn-primary {
    background-color: var(--primary-color);
    color: var(--white);
}

.btn-primary:hover {
    background-color: #3a7bc8;
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(74, 144, 226, 0.3);
}

.btn-secondary {
    background-color: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

.btn-secondary:hover {
    background-color: var(--primary-color);
    color: var(--white);
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(74, 144, 226, 0.3);
}

.hero-image {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
    animation: slideInRight 0.8s ease-out 0.3s both;
}

@keyframes slideInRight {
    from {
        opacity: 0;
        transform: translateX(50px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.app-screenshot {
    max-width: 100%;
    height: auto;
    display: block;
    transition: transform 0.3s ease;
    object-fit: contain;
}

.app-screenshot:hover {
    transform: scale(1.02);
}

/* Hero Image 响应式显示控制 */
/* 默认隐藏移动端图片，显示PC端图片 */
.hero-image-mobile {
    display: none;
}

.hero-image-desktop {
    display: flex;
}

/* 在移动端（992px以下）显示移动端图片，隐藏PC端图片 */
@media (max-width: 992px) {
    .hero-image-mobile {
        display: flex;
        margin-top: 40px;
    }
    
    .hero-image-desktop {
        display: none;
    }
    
    .app-screenshot {
        max-width: 95%;
        margin: 0 auto;
    }
}

/* 功能介绍样式 */
.features {
    padding: 100px 0;
    background: linear-gradient(135deg, var(--bg-color) 0%, rgba(240, 245, 255, 0.5) 100%);
    transition: background 0.3s ease;
    position: relative;
    overflow: hidden;
}

/* 常见问题页面样式 */
.faq-page {
    padding: 110px 0 80px;
    background-color: var(--white);
    transition: background-color 0.3s ease;
}

.faq-page h1 {
    text-align: center;
    font-size: 42px;
    font-weight: 700;
    margin-bottom: 50px;
    color: var(--primary-color);
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: 0 2px 4px rgba(74, 144, 226, 0.1);
    letter-spacing: 0.5px;
}

.faq-container {
    max-width: 1000px;
    margin: 0 auto;
    background-color: var(--white);
    border-radius: 12px;
    box-shadow: var(--box-shadow);
    overflow: hidden;
    transition: all 0.3s ease;
}

.faq-iframe {
    width: 100%;
    height: 800px;
    border: none;
    display: block;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .faq-page h1 {
        font-size: 32px;
    }
    
    .faq-iframe {
        height: 600px;
    }
}

@media (max-width: 480px) {
    .faq-page {
        padding: 80px 0 60px;
    }
    
    .faq-page h1 {
        font-size: 28px;
        margin-bottom: 30px;
    }
    
    .faq-iframe {
        height: 500px;
    }
}

.features::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color) 0%, var(--secondary-color) 100%);
}

.features h3 {
    text-align: center;
    font-size: 36px;
    font-weight: 700;
    margin-bottom: 70px;
    color: var(--primary-color);
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: 0 2px 4px rgba(74, 144, 226, 0.1);
    letter-spacing: 0.5px;
    transition: all 0.3s ease;
    position: relative;
    display: inline-block;
    left: 50%;
    transform: translateX(-50%);
}

.features h3::after {
    content: '';
    position: absolute;
    bottom: -15px;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 3px;
    background: linear-gradient(90deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    border-radius: 2px;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 25px;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.feature-item {
    background-color: var(--card-bg);
    padding: 35px;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    border: 1px solid rgba(74, 144, 226, 0.1);
    position: relative;
    overflow: hidden;
}

.feature-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: linear-gradient(180deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    transition: transform 0.4s ease;
    transform: scaleY(0);
    transform-origin: bottom;
}

.feature-item:hover {
    transform: translateY(-8px) scale(1.02);
    box-shadow: 0 12px 30px rgba(74, 144, 226, 0.2);
    border-color: rgba(74, 144, 226, 0.3);
}

.feature-item:hover::before {
    transform: scaleY(1);
}

.feature-item .feature-image {
    width: 60px;
    height: 60px;
    margin-bottom: 20px;
    border-radius: 8px;
    background-color: rgba(74, 144, 226, 0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
    transition: all 0.3s ease;
}

.feature-item:hover .feature-image {
    transform: scale(1.1) rotate(5deg);
    background-color: rgba(74, 144, 226, 0.2);
}

.feature-item h4 {
    font-size: 22px;
    font-weight: 600;
    margin-bottom: 18px;
    color: var(--primary-color);
    transition: color 0.3s ease;
    position: relative;
    z-index: 2;
}



.feature-item p {
    color: var(--text-light);
    font-size: 16px;
    line-height: 1.75;
    transition: color 0.3s ease;
    position: relative;
    z-index: 2;
}

/* 日记本介绍样式 */
.diary {
    padding: 80px 0;
    background-color: var(--white);
    transition: background-color 0.3s ease;
}

.diary h3 {
    text-align: center;
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 60px;
    color: var(--text-color);
    transition: color 0.3s ease;
}

.diary-content {
    display: flex;
    align-items: center;
    gap: 60px;
}

.diary-text {
    flex: 1;
}

.diary-text p {
    font-size: 18px;
    color: var(--text-light);
    line-height: 1.8;
    transition: color 0.3s ease;
}

.diary-visual {
    flex: 1;
    display: flex;
    justify-content: center;
}

.diary-preview {
    width: 300px;
    height: 200px;
    background-color: var(--bg-color);
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    transition: background-color 0.3s ease;
}

/* 隐私安全样式 */
.security {
    padding: 80px 0;
    background-color: var(--bg-color);
    transition: background-color 0.3s ease;
}

.security h3 {
    text-align: center;
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 60px;
    color: var(--text-color);
    transition: color 0.3s ease;
}

.security-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 40px;
    max-width: 900px;
    margin: 0 auto;
}

.security-item {
    text-align: center;
    padding: 30px;
    background-color: var(--card-bg);
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    transition: background-color 0.3s ease;
}

.security-item h4 {
    font-size: 22px;
    font-weight: 600;
    margin-bottom: 15px;
    color: var(--primary-color);
    transition: color 0.3s ease;
}

.security-item p {
    color: var(--text-light);
    font-size: 16px;
    line-height: 1.7;
    transition: color 0.3s ease;
}

/* 下载区域样式 */
.download {
    padding: 100px 0;
    background-color: var(--white);
    text-align: center;
    transition: background-color 0.3s ease;
    position: relative;
}

.download::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color) 0%, var(--secondary-color) 100%);
}

.download h3 {
    text-align: center;
    font-size: 36px;
    font-weight: 700;
    margin-bottom: 70px;
    color: var(--primary-color);
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: 0 2px 4px rgba(74, 144, 226, 0.1);
    letter-spacing: 0.5px;
    transition: all 0.3s ease;
    position: relative;
    display: block;
    margin-left: auto;
    margin-right: auto;
    width: fit-content;
}

.download h3::after {
    content: '';
    position: absolute;
    bottom: -15px;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 3px;
    background: linear-gradient(90deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    border-radius: 2px;
}

.download p {
    font-size: 20px;
    color: var(--text-color);
    margin-bottom: 40px;
    transition: all 0.3s ease;
    margin-top: -30px;
    text-align: center;
    font-weight: 500;
    letter-spacing: 0.5px;
}

.download-platforms {
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
}

.download-btn {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 14px 24px;
    text-decoration: none;
    border-radius: 50px;
    font-weight: 600;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    font-size: 15px;
    min-width: 140px;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

/* 浅色模式下的按钮样式 */
.download-btn.ios {
    background-color: var(--white);
    color: var(--text-color);
    border: none;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
}

.download-btn.ios:hover {
    background-color: var(--primary-color);
    color: var(--white);
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(74, 144, 226, 0.3);
}

.download-btn.android {
    background-color: var(--white);
    color: var(--text-color);
    border: none;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
}

.download-btn.android:hover {
    background-color: var(--primary-color);
    color: var(--white);
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(74, 144, 226, 0.3);
}

/* 按钮点击效果 */
.download-btn:active {
    transform: translateY(-1px);
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
}

/* 深色模式下的按钮样式 */
[data-theme="dark"] .download-btn {
    background-color: var(--card-bg);
    color: var(--text-color);
    border: none;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
    gap: 10px;
    padding: 14px 24px;
    font-size: 15px;
    min-width: 140px;
}

[data-theme="dark"] .download-btn.ios:hover {
    background-color: var(--primary-color);
    color: var(--white);
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(74, 144, 226, 0.3);
}

[data-theme="dark"] .download-btn.android:hover {
    background-color: var(--primary-color);
    color: var(--white);
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(74, 144, 226, 0.3);
}

.platform-icon {
    width: 24px;
    height: 24px;
    vertical-align: middle;
}

/* 确保img元素的平台图标正确显示 */
.platform-icon img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

/* 苹果图标样式 */
.apple-icon {
    background-image: url('assets/brand/apple.png');
    background-size: contain;
    background-repeat: no-repeat;
    background-position: center;
    width: 24px;
    height: 24px;
}

/* 深色模式下的苹果图标使用白色版本 */
[data-theme="dark"] .apple-icon {
    background-image: url('assets/brand/apple_white.png');
}

/* 用户评价样式 */
.testimonials {
    padding: 100px 0;
    background-color: var(--bg-color);
    transition: background-color 0.3s ease;
    position: relative;
}

.testimonials::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color) 0%, var(--secondary-color) 100%);
}

.testimonials h3 {
    text-align: center;
    font-size: 36px;
    font-weight: 700;
    margin-bottom: 70px;
    color: var(--primary-color);
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: 0 2px 4px rgba(74, 144, 226, 0.1);
    letter-spacing: 0.5px;
    transition: all 0.3s ease;
    position: relative;
    display: inline-block;
    left: 50%;
    transform: translateX(-50%);
}

.testimonials h3::after {
    content: '';
    position: absolute;
    bottom: -15px;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 3px;
    background: linear-gradient(90deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    border-radius: 2px;
}

.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.testimonial-item {
    background-color: rgba(30, 30, 40, 0.9);
    padding: 15px;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    border: none;
    position: relative;
    display: flex;
    flex-direction: column;
    min-height: 220px;
}

.app-icon {
    position: absolute;
    top: 10px;
    right: 10px;
    width: 24px;
    height: 24px;
    opacity: 0.7;
}

.app-icon img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.testimonial-item:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.4);
}

.testimonial-content {
    display: flex;
    flex-direction: column;
    gap: 8px;
    flex: 1;
}

.testimonial-header {
    margin-bottom: 0;
}

.testimonial-author {
    font-size: 14px;
    font-weight: 600;
    color: #ffffff;
    margin: 0;
}

.testimonial-rating {
    margin: 0;
    font-size: 16px;
    color: #FFD700;
}

.testimonial-text {
    color: #e0e0e0;
    font-size: 13px;
    line-height: 1.5;
    margin: 0;
    font-style: normal;
    flex: 1;
}

.testimonial-date {
    font-size: 11px;
    color: #888;
    margin-top: 8px;
    text-align: left;
}



/* 页脚样式 */
.footer {
    background-color: #1a1a1a;
    color: var(--white);
    padding: 60px 0 30px;
    transition: all 0.3s ease;
}

.footer .container {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.footer-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin-bottom: 30px;
    text-align: center;
}

.footer-logo {
    margin-bottom: 20px;
}

.footer-logo .logo-link {
    display: flex;
    align-items: center;
    text-decoration: none;
    color: var(--white);
    transition: all 0.3s ease;
}

.footer-logo .logo-link:hover {
    transform: translateY(-2px);
}

.footer-logo .logo-img {
    height: 40px;
    width: auto;
    margin-right: 12px;
    filter: brightness(1.2);
}

.footer-logo .logo-text {
    font-size: 24px;
    font-weight: 600;
    color: var(--white);
    transition: color 0.3s ease;
}

.footer-description {
    color: #999;
    font-size: 16px;
    line-height: 1.5;
    margin: 0;
    max-width: 500px;
}

.footer-bottom {
    text-align: center;
    color: #fff;
    font-size: 14px;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    width: 100%;
}

.footer-link {
    color: #fff;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-link:hover {
    color: var(--primary-color);
    text-decoration: underline;
}

/* 深色模式适配 */
[data-theme="dark"] .footer {
    background-color: #121212;
}

[data-theme="dark"] .footer-logo .logo-text {
    color: #fff;
}

[data-theme="dark"] .footer-description {
    color: #ccc;
}

[data-theme="dark"] .footer-bottom {
    color: #ccc;
    border-top-color: rgba(255, 255, 255, 0.2);
}

[data-theme="dark"] .footer-link {
    color: var(--primary-color);
}

[data-theme="dark"] .footer-link:hover {
    color: var(--secondary-color);
}

/* 响应式设计 */
@media (max-width: 992px) {
    .hero .container {
        flex-direction: column;
        text-align: center;
    }

    .hero-image {
        margin-top: 50px;
        justify-content: center;
    }

    .diary-content {
        flex-direction: column;
        text-align: center;
    }

    .nav-menu {
        display: none;
    }
}

@media (max-width: 768px) {
    .hero h2 {
        font-size: 32px;
    }

    .hero p {
        font-size: 16px;
    }

    .download-buttons {
        flex-direction: column;
        align-items: center;
    }

    .btn {
        width: 100%;
        text-align: center;
    }

    .features h3,
    .diary h3,
    .security h3,
    .download h3 {
        font-size: 28px;
    }

    .features-grid {
        grid-template-columns: 1fr;
    }

    .security-content {
        grid-template-columns: 1fr;
    }

    .download-platforms {
        flex-direction: column;
        align-items: center;
    }

    .download-btn {
        width: 100%;
        max-width: 300px;
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .hero {
        padding: 100px 0 60px;
    }

    .hero h2 {
        font-size: 28px;
    }

    /* .app-screenshot {
        width: 250px;
        height: 420px;
    } */

    .features,
    .diary,
    .security,
    .download {
        padding: 60px 0;
    }
}